import java.util.Scanner;

public class main {
    private static void func() {
        System.out.println("1.查找图书");
        System.out.println("2.借阅图书");
        System.out.println("3.归还图书");
        System.out.println("4.查看图书");
        System.out.println("0.退出系统");
    }
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请选择操作");
        while(true) {
            func();
            int n = scanner.nextInt();


        }
    }


}
